a lot of guys just don't understand what crossfit is all about
crossfit is simply team exercising but utilizing more X reps in Y amount of time
it isn't bodybuilding. it is a mix of powerlifting and cardio. but it is just like anything else in life, if you do it right and push yourself you will improve. and yes genetics help just like anything else.
my issues with crossfit is that it is very expensive.. usually 4-5X what a gym costs per month. and that I like to workout solo with my headphones in without being bothered
the benefits of crossfit is you can lift like a gorilla and they don't care. you won't have the manager yell at you for dropping weights, or using chalk, or screaming, etc. it is more of a garage/backyard workout environment.